レンチニン酸よりグルタミン酸残基を除去した新含硫アミノ酸(desglutamyl-lentinic acid)のピリドキサ-ルリン酸との複合体形成能

概要

論文の詳細を見る
γ-Glutamyl moiety of lentinic acid found in fruit bodies of Lentinus edodes was removed by the action of Lentinus γ-glutamyltransferase and the resultant compound was isolated in rod-shaped crystals with a 62% yield (mp 194°C decomp.). Elementary composition of the isolated compound (Found: C, 24.06; H, 4.30; O, 31.56; N, 4.01; S, 36.07%) was in good agreement with that expected for desglutamyl-lentinic acid (DGLA, C7H15O7N1S4). Incubation with pyridoxal phosphate (PALP) incurred loss of the substrate capacity of DGLA for Lentinus C-S lyase; DGLA was otherwise among the best substrate for the lyase. Spectrophotometric data showed that DGLA formed a stable complex with PALP with association constant of about 1.2×105M-1; complex thus arisen exhibited an absorption maximum at 330 nm, which is attributable to formation of an aldamine bond between DGLA and PALP. The complex was only sluggishly dissociable, if not entirely undissociable, so as to be separated from both free DGLA and PALP on thin layer chromatogram. Additionally, tryptophanase and glutamate-oxaloacetate transaminase were inactivated by incubation with DGLA, and apoproteins from these enzymes were not reactivated by addition of DGLA-PALP complex.
社団法人日本農芸化学会の論文